Police are investigating the assault of a number of students at a Secret Harbour high school.
Sometime between 10:30am and 11:00am on Tuesday, two youths, one who is known to the school, attended Comet Bay College.
"At this time, we have become aware of two incidents where other students were assaulted by one of the two youths," a WA Police spokesperson said.
It's understood the pair threatened to return to the college with weapons.
"Mandurah Police are investigating the circumstances surrounding the incidents and the investigation is ongoing," the WA Police spokesperson said.
"Part of the ongoing investigation is liaising with the families of the students who were assaulted, to confirm whether they wish to make a formal complaint."
Security will be onsite on Wednesday as a precaution.
The Department of Education has been contacted for comment.
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